Geographically related information such as weather, traffic, real estate listings, restaurant information, military weapons movement, base map upgrades, evacuation routes, and terrorist attack avoidance routes are among the types of information that may be delivered by wireless communication. Typically, however, this information needs to be tailored to specific geographic locations to be most useful to the receiver of the information. For example, anyone who is traveling by land, sea, air, by vehicle, or on foot requires geographic information to get from a starting point to their destination. This basic geographic information is available, for example, from a compass, a road atlas, or a chart. Electronic forms of geographic information are available from devices that indicate position, direction, velocity, and altitude. However, if additional information about a particular location is required, additional interaction is necessary. This is particularly inconvenient for the person engaged in operating a vehicle.
It is becoming increasingly common for individuals to carry various forms of devices for receiving such information. While a local radio broadcast is the most direct approach for transmitting localized information, hand held computing devices now allow individuals to receive and extract information available, for example, from the Internet. Such computer technology may take the form of a laptop computer with a wireless receiving device or a wide area network (WAN) enabled PDA, e.g., a Palm Pilot™, that can receive Internet broadcasts. However, the computer technology cannot easily distinguish whether the broadcasts are for local geographic areas or for a remote geographic location. As a result, the user must analyze the broadcast to determine if the information is applicable to the users current geographic location.
It is known for a receiver, such as a PDA, to obtain location specific information from a localized broadcaster, provided the receiver includes a geographic positioning system. One such method is disclosed in U.S. Pat. No. 6,122,520 that describes a receiver for determining a present location, transmitting location coordinates to a network, and receiving location information corresponding to the transmitted location coordinates. The problem with this type of scheme for obtaining location specific information is that the receiver must include a transmitter to transmit the receiver's location to a provider of customized location information. As a result, the receiver needs additional circuitry to provide transmitting capability. In addition, the receiver needs to provide considerably more power to enable transmission of location coordinates to a network. Consequently, a mobile, handheld receiver for obtaining customized location information will suffer from reduced operating times and require more frequent recharging or battery replacement compared to a receiver-only device. Furthermore, in applications such as military operations, it may be important to use receivers that do not need to transmit to help avoid detection of a receiver's position. Accordingly, a receiver-only device can provide stealth advantages over more easily detected receive/transmit devices.
A tailored information delivery scheme using a one-to-one (network to single device) method, wherein each device requests information from the network, suffers from the drawback of requiring the network to deliver an individualized stream of information to each device within a service area. This is true even if the information being requested, such as geographically relevant information, is identical for multiple devices in the broadcast area, at the same point in time. This is a bandwidth expensive and inefficient method to accomplish the delivery of the individualized information. Therefore, there exists a need to inexpensively and efficiently deliver, using a passive, one to many topology (one network to many receivers simultaneously), geographic specific information to multiple receivers within a network. Such a scheme would allow better network resource allocation and therefore, would be much less expensive and bandwidth efficient to operate for the network.
Accordingly, a need exists for a method and system for receiving location specific information that does not require transmitting location information to a provider of the location specific information. In addition, a need exists for a system that allows a receiver to determine its location and reject or accept broadcasted location information based on the receiver's location. Further, there is a need for a system that can distinguish between geographically remote or geographically local information, and provide a user with information that is geographically oriented.